The present invention relates to integrated circuit chips and, more particularly, to mixed signal integrated circuit chips.
Integrated circuits or ICs are extensively used in all types of today""s electronic devices. One trend in IC design and manufacturing is the miniaturization of the various components of an IC. Another trend in IC design and manufacturing is the consolidation of functionality traditionally provided by several ICs into one IC. By consolidating functionality into fewer and fewer ICs combined with the continued trend in miniaturization, the overall physical space occupied by such an IC within an electronic device is reduced. Such reduction also reduces the overall size of the electronic device. The consolidation of functionality is typically accomplished by combining same signal type circuits since most electronic devices utilize the same type of signals. This is not, however, always the case as a few electronic devices benefit from the consolidation of functionality of different signal sections.
One class of electronic devices is television signal processing devices. Television programming for the home viewer is available from many sources such as, terrestrial broadcasting, cable (CATV) distribution, satellite broadcasting (e.g. DBS) or the like. The television programming, in the form of television signals, may be provided in an analog and/or digital format. Depending on the transmitting medium, the analog and digital formats may vary. For example, different modulating schemes may be used for transmitting digital television signals. Various television signal processing devices such as televisions, set-top boxes, and the like must be able to process both analog and digital television signals and their attendant formats.
ICs for dual function analog and digital television signals are thus typically designed to have either analog signal circuits for processing analog signals and digital signal circuits for processing digital signals. However, in keeping with the trend for miniaturization and consolidation of functionality, television signal processing ICs for dual function analog and digital television signal processing include analog and digital circuitry for the analog and digital signals. ICs utilizing both analog and digital signals are termed mixed signal ICs.
All ICs have a plurality of pins or terminals for input and output (I/O). Some of the pins are dedicated to resetting various circuits of the IC for synchronization. A problem with mixed signal ICs is that several I/O pins of the plurality of I/O pins are necessary in order to provide signals to reset both the analog circuitry and the digital circuitry. Since it is desirable to reduce the overall number of I/O pins in an IC, it is desirable to utilize, and thus have, only one reset I/O pin for a mixed signal IC.
The present invention is a system and method for resetting both the analog and digital circuits of a mixed signal integrated circuit utilizing a single reset pin/signal.
In one form, the present invention is an integrated circuit having a first section for processing an analog signal and a second section for processing a digital section. A single input pin is operable to provide a single pin reset signal to the integrated circuit for activating a reset condition of both the first and second sections and for terminating the reset condition of both the first and second sections.
In another form, the present invention is a method for resetting an integrated circuit. The method includes: a) providing a reset signal to the integrated circuit via a single input pin; b) activating a reset condition in an analog signal processing section of the integrated circuit in response to the reset signal; c) activating a reset condition in a digital signal processing section of the integrated circuit in response to the reset signal; d) terminating the reset condition of the analog signal processing section in response to the reset signal; and e) terminating the reset condition of the digital signal processing section in response to the reset signal.